This background pattern contains a seamless texture of bark. It's not very realistic, but I think it looks quite nice.
Source V. Hartikainen
A seamless paper background colored in pale yellow.
Source V. Hartikainen
More tactile goodness. This time in the form of some rough cloth.
Source Bartosz Kaszubowski
A seamless chequerboard pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
This one is amazing, truly original. Go use it!
Source Viahorizon
Zero CC tileable yellow craft paper; scanned and made by me. CC0
Source Sojan Janso
Original minus the background
Source Firkin
Dark pattern with some nice diagonal stitched lines crossing over.
Source Ashton
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
A seamless pattern the starting point for which was a 'colour modulo' texture in Paint.net.
Source Firkin
Wild Oliva or Oliva Wilde? Darker than the others, sort of a medium dark pattern.
Source Badhon Ebrahim
Sounds like something from World of Warcraft. Has to be good.
Source Tony Kinard
I’m guessing this is related to the Sony Vaio? It’s a nice pattern no matter where it’s from.
Source Zigzain
A subtle shadowed checkered pattern. Increase the lightness for even more subtle sexiness.
Source Josh Green
Derived from an image that was uploaded to Pixabay by mdmelo.
Source Firkin
A slightly more textured pattern, medium gray. A bit like a potato sack?
Source Bilal Ketab
A pattern derived from repeating unit cells each derived from part of a fractal rendering in paint.net.
Source Firkin
Dare I call this a «flat pattern»? Probably not.
Source Dax Kieran
A seamless pattern the starting point for which was a 'colour modulo' texture in Paint.net.
Source Firkin